DUBLIN, Calif., Oct. 24, 2012 (GLOBE NEWSWIRE) -- Astex Pharmaceuticals, Inc. (Nasdaq:ASTX), a pharmaceutical company dedicated to the discovery and development of novel small molecule therapeutics, announced that it has initiated an open label, randomized, controlled, multi-center, Phase 2 clinical trial, evaluating HSP90 inhibitor AT13387 in anaplastic lymphoma kinase positive (ALK +) non-small cell lung cancer patients or other potentially crizotinib-sensitive NSCLC patients who have been receiving crizotinib. The trial will evaluate AT13387 as both single agent and in combination with crizotinib in these patients. The AT13387 study will consist of three parts. Part A is a lead-in, single arm, dose escalation segment of the trial in patients with NSCLC who have already been receiving crizotinib, to establish the Maximum Tolerated Dose (MTD) of the combination. Once the MTD is defined in Part A, and depending on the patient's response to crizotinib, Parts B and C will ensue in which patients will be randomized to continue to receive crizotinib alone, AT13387 alone, or the combination of AT13387 with crizotinib. "This is the most comprehensive study designed to date to investigate the efficacy and safety of an HSP90 inhibitor in patients who are sensitive to an ALK+ inhibitor," said Mohammad Azab, MD, chief medical officer. "The study will permit us to identify a clear role of HSP90 inhibition by AT13387 both as a single agent and in combination with an ALK+ inhibitor in the treatment of NSCLC." About the Study The primary objective of Part A of this trial is to determine the safety and tolerability of combination therapy with AT13387 and crizotinib and to determine the MTD for Parts B and C. The primary objective in Part B will be to compare the efficacy by response rate between continued administration of single agent crizotinib versus the combination of AT13387 plus crizotinib in patients who were treated for at least 8 weeks with crizotinib and have not yet progressed. Lastly, the primary objective of Part C will be to test the efficacy by response rate of single agent AT13387 and the combination of AT13387 and crizotinib in patients who progressed on treatment with crizotinib.